Telephone time-signal repeating system



4 Sheets-Sheet, 1.

(No Model.)

' J. M. ORAM.

TELEPHONE TIME SIGNAL REPEATING SYSTEM. No. 287,710. Patented Oct. 30, 1883.

l I r N u H w WITNESSES INVENTOR wzyw g Jaw ATTORNEYS.

(No Model.) 4 Sheets-Sheet 2.

J. M. DRAM.

TELEPHONE TIME SIGNAL REPEATING SYSTEM.

No. 287,710. Patented Oct. 80, 1883.

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4 SheetS -Sheet 4.

(Nb Model.)

Patented Oct. 80, 1883'.

III

WITNESSES ATTORNEYS.

UNITED STATES {PATENT I OF ICE.

JOHN M. ORAM, OF DALLAS, TEXAS.

TELEPHONE TIME-SIGNAL REPEATING SYSTQVI.

SPECIFICATION forming part of Letters Patent No. 287,710, dated October so, 1883,

' Application filed January 6, 1883. (No model.)

To all whom it may concern.-

Be it known that I, JOHN M. ORAM, of Dallas, in the county of Dallas and State of Texas,

have invented a new and useful Improvement in Telephone Time-Signal Repeating Systems; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing, forming a part of this specification.

Myinvention is designed to provide a method by which all of the subscribers of a telephonic system are put in possession of the correct time from a single standard clock by continuous signals repeated throughout all the minutes of the day, and without the necessity for electric clocks at the subscribers end of the line, thus avoiding the necessity for a multitude of such clocks, and the expense and complication incidental to their use.

In carrying out my invention I employ a single clock of the class known as a repeateri. 0., one that strikes (or makes a mechanical'adjustment other than the movement of the hands) for every hour and minute in the day, which stroke or mechanical adjustment, in accordance with my invention, is made to transmit signals over the telephonelines to the receivers, and which signals are, by variation of intervals between them, (or other measures,) made to convey a significance to the subscriber by either the sound of the receivers diaphragms or by strokes on the bells of the subscribers, as hereinafter more fully described.

Figure. 1 of the drawings represents a diagram in which the time-signals to the subscribers are made simply by the sound of the diaphragms of the receiversi Fig. 2 represents a diagram in which the signals are made upon the subscribers bells so as to be generally audible; and Fig. 3 is a diagram representing a simplified modification of my invention in which a local battery and the normal ground-circuit are dispensed with,as hereinafter referred to. Figs. 4, 4, 4", and 4 represent the internal construction of a repeating-clock such as I use with my invention.

Referring to Fig. 1, A is a repeating-clock, which is organized to repeat the time upon the following arbitrary system: The hours it I strikes at intervals 'of two seconds of time,

the'division of ten minutes it strikes at inter.

vals of one second of time, and the division of minutes it strikes at intervals of two-thirds of a second. Thus at three o clock and fifty-nine minutes, the clock would strike three strokes at intervals of two seconds, five strokes at intervals of one second, and nine strokes at intervals of two thirds of a second, which may be illustrated thus:

Then the next minute would be four oclock,"

audible signal, but only make a mechanical adjustment to close and break an electrical current (or vary the tension of an electrical circuit) in accordance with such subdivsion of time.

As shown, the diagram in Fig.1 represents a central office, with the exception of that portion to the left of the breaks in the linesat b, and the receiver to the left of this represents one of the subscribers stations. H is the main battery; G, the local battery, whose circuit is controlled by the clock; E, an electromagnet; B, its armature; N C,'are back and front contacts; a aa", lines for three subscribers, and of which theremay be any number; I I,

the normal ground-circuit, or circuit through which callimpulses coming from the subscriber to the central office find their way to the earth. 1-3 5 are the annunciators for the three subscribers, and 2 4 6 are'the spring-jacks of the switch-board, by means of which two subscribers may be connected by plugs in the usual manner. The repeatingclock Ais here shown in the central oflice; but it is obvious that its 1ine-wires may be extended sufficiently to locate it in a jeweler s store, or in an observae tory, where it may be more conveniently kept under constant supervision as to correctness. Now, this clock makes and breaks the circuit of local battery G, controlling the electro-magnet E of the central office, and said circuit is nor mally broken, so that the armature B rests back upon the back contact, N, from the tension of I00 its spring, whereby the normal ground-circuit I I is closed, and gives to each subscribers line an outlet to'the ground atthe central office.

"all the lines a a, a, producing in the receiver R at the subscribers end a sound by movement of the diaphragm, and thence passing to earth. This movement of the diaphragm is the audible time-signal for the subscribers, 'andas the clock divides such movements into groups with different intervals of time between-as in the instance given, i

. flh -the subscriber knows that it is minute of four.

fifty-nine minutes past three oclock, or one These signals do not interfere with the use of the telephone fortalking purposes, because the spring-jacks of any two subscribers who may happen to be talking to each other are at that time discohnected from the rest of the system. With this arrangement of mysystem, when the signals aresimple sounds of the diaphragms, in the subscribers receivers made significant as to time by the arbitrary intervals of ,time between them, only a weak battery-current is required, and this is not sufiicient to throw down the annunoiators 1 Formakingmy inventionavailableforstriking a bell in the office of each subscriber, the

current necessary to do this is a much stronger one,-and as this would throw down all, or at least a part, of the annuciators of the central I office, and thus produce great confusion and 4. provision for overcoming this difficulty. I

embarrassment, I have shown in Fig, 2 a

employ between the magnet E and its armature Ba spring, 0, which, when armature B rests against back stop, N, occupies a position between the stop G and the armature B, but does not touch either. This spring 0, I connect by wire 1 with the bra-nches'a a a of the subscribers lines, while the armature B is connected by wire I with the branches. J J J of the subscribers lines. Now, then, two sets of wires, a a a and J J J, are connected,

respectively, upon-opposite sides of the annunciators'l 3 5, and any current which passes through these two sets of branches from the central oflice is so weakened in the electromagnets of. the annunciators so as to have no effect on the latter. With this arrangement, when the clockeloses the local-battery circuit and charges electro-magnet E, armature B moves forward tillit strikes spring 0, and then both move forward together till they both strike the front contact, 0. The main-battery current, then passing through; both B and'O-and the branches 0:, a a and J J J, has no eflect upon the doors of the annunciators,

but nevertheless passes into the several subscribers lines in sufficient energyto ring the bells at the subscribers stations, each of which by its hammer in accord bells is tapped upon system .of signals ance with the prearranged as made by the generally audible through the room of each subscriber. again against contact N, it leaves the spring O and renews the normal ground-circuit 1'. To compensate for the resistance of the electromagnet of the annunciator, which we will assume to be 25, differential. resistances are placedin the branches 0. a a? and J JJ to balance the current. Thus for line a, 50 is placed in the branch J ,-which, with. the 25 of clock, which bell-signals are As the armature B moves back the annunciator-magnet, just balances the resistance in branch a Resistances may also be placed in the shorter lines to equalize the efl'ect of the current on all the bells.

In Fig. 3 is shown in heavy black lines how the normal ground-circuit and local battery may be dispensed with and the main-battery circuit controlled direct by the clock and distributed to the several subscribers lines.

I .am aware that it has been proposed .to utilize telephone-lines for signaling time to a setv of electrical clocks, and I do not claim any such arrangement. My invention is distinctive in the fact that only one clock is used, and that is a repeater, and thesignals sent to the subscribers are not made to act upon electric clocks at such points to give their hands aprogressive movement; but said signals are audible signals, possessing suificient significance as to indicate of themselves the time continuously through the day. This permits the telephone-circuits tobe utilized just asthey stand without complication or interference, and dispenses with the cost of a great number of electrical clocks.

In my invention the repeating-clock need not necessarily make and break the circuit by direct electrical connections, but may varythe electrical. condition of the line through sound-waves in the air acting upon a transmitter of ordinary construction, thereby sending inducedor secondary currents over the line, as shown in dotted lines in Fig. .1.

r In order to make my invention sufficiently clear as to enable anyone skilled in the art to make and use it, I deem it best to describe one form of repeating-clock, of which only a general outline is shown in Figs. 1, 2, 3.

Referring to Fig. 4, X represents a clock proper or timing mechanism, which is arranged to complete the circuit h and charge the magnet 0" every minute in the .day. This clock has its repeating mechanism shown extraneous to it, and has a battery-circuit', h,

within it, which-ishere. represented diagrammatically.

K S N is a small electric motor, which is driven by a separate battery and'circuit, (not shown,) and which may be replaced by a spring or weight movement. The clock X gives the time and breaks circuit hat regular intervals of one minute,while the motor K S-' N supplies the power for shifting and adjusting the repeating mechanism by rotating shaft K. \Vhenever (every minute) the clock makes circuit h and charges magnet 1 armature j is attracted, and this pushes bodily the slidebar H", and simultaneously throws clutch .T* to or gagement with arm L and takes arm K* out of the slot in disk T (for side view of disk I see Fig. 43,) which disk is on main shaft carrying repeating-cylinder A". Theresult is that the motor. through the clutch J turns the shaft of arm Lflan d this shaft, through a diminishing train of wheels, slowly causes the cylinder A" to revolve one revolution, after which spring Z pulls stop K* into slot of disk I and stops the repeating-cylinder. On the repcating-cylinder are three groups of pins, one group, 0", being arranged in rows, which rows contain pins from one to twelve, and between which pins of each row a space representing two seconds of time in the revolution of the cylinder is left.

At p is shown the group of pins representing the ten-minute division, and these are arranged in rows from one to five, and have a space between them representing a second of time.

At (1 is shown the group of pins of the minute-subdivision, arranged in rows from one to nine.

B B B" are three levers, whose ends next to the cylinder are struck by the pins 0 19* if, and the levers deflected thereby. As shown, lever B ism the row of three pins of the hourgroup, 13* is in the row of five pins of the tenminute division, and the lever B is in the row of nine of the lllllllltG-SllbdlVlSlO11, so that a revolution of the cylinder would deflect lever B three timesat intervals of two seconds, lever B five times at intervals of one second, and lever 3 nine times at intervals of twothirds of a second; and these levers being made one of the terminals of battery-circuit G of Fig. 1., and the bar M, Fig. 4, another terminal of said circuit, it is easily seen how the local current in Fig. l'is broken into the significant signals of time. To shift the lovers B B to correspond with the passage of each minute of time the following mechanism is provided: To each of said levers B" 13* B is attached a slide-bar, 0" 0 0 of which 0" has twelve ratchet-tectli corresponding to the twelve rows of pins, 0 and of which 0* has live ratchet-teeth corresponding to the five rows of pins, 9 while 0 has nine teeth corresponding to the nine rows of teeth, (1 Each of these toothed slides is drawn to the right by spiral springs I)" b b, and as they are moved against the tension of said springs they are held to said adjustment by separate detents l), &c. The lower slide, 0", represents minutes, and is acted on every minute, and is closest to the cylinder A. The next slide, 0*, above is farthest away from the cylinder, and isacted on once in ten minutes, and the upper slide, 0, is still farther from the cylinder,

and is acted on once every hour, thus giving them the proper adjustment in relation to the.

repeating pins-0 p g .to strike the successive times of day in distinctive signals. For giving this adjustment. to the slides 0 0* 0 the end of cylinder A is provided with a spring-cam, F Fig. 4, pivoted at m and forced outwardly by spring 9* 'till its upper end is held by a stop. The wing If of this cam is inclined to the plane of revolution, and by engaging with the teeth of the slide-bars 0 0" 0 moves them along. and 0*, at the end of these series of teeth, there are slots 8 s, Fig. 4", whose function is as follows: Each revolution of cylinder A causes the wing k of cam 'F' to enter a tooth of the lower bar, 0 and move it one tooth.

After nine successive movements of this bar the slot 3 at the end of the series comes into the plane of wing W, and the latter is free from the action of spring to move outward still farther and move the second bar, 0*. Then, again, at the end of five such motions of bar 0 the slot 8 in said bar coincides with slot 8 of bar 0 and the wing h of the cam can penetrate still deeper and move not only bars 0 and 0*, but also the bar 0 which latter is moved only once in sixty movements of bar 0 and indicates the hours. ders a (4* a of the toothed slides strike detents D", 810., the latter are thrown up and caught by spring-hook E until arm N on the end of cylinder A comes around and pullsthe hooks away from the detents. As shown, the strokes of levers B B on bar M are made to control the local-battery circuit G and operate the armature E of Fig. 1; but when the In the lower slides, 0 1

Vhen the shoulsignals are to be transmitted through air-vibrations impinging againsta transmitter the stems 0 c c are extended and made'to strike the bells shown in dotted lines.

Having thus described by inventiomwhat I claim as new is 1. The method herein described of supplying standard time to any number of subscribers in a telephonic system, which consists in continuously making and breaking (or varying the electrical condition of the main circuit into significant signals, having different intervals 'of time between the signals of the several groups denoting different subdivisions of time, whereby the audible signals-are made recognizable and significant as to time in each receiver, separate receiving-clocks at each subscribers station are dispensed with, and the simplicity and efiiciency of the telephonic system preserved without interference or inter ruption, as described.

2. The method of striking standard ti me upon' the bells of; any number of subscribers in a telephone systcm,whichconsists in continu ously making and breaking the electric current into recognizable signals, having different intervals of time between the signals of the several groups, and dividing this current at the central ofiice upon opposite sides of the annuneiators to prevent the dropping of the annunciatordoors from said signals, as described.

3. The combination, with a telephone system and a; suitable battery, of acloek, constructed as described, to repeat continuously throughout the whole day, and breakor vary I 5 the current on the line into recognizable sigoperated by said circuit, a main-line circuit,

and the armature B and springO, connected, respectively, to branch lines leadingto the opposite sides of the subscribers annuneiators, as and for the purpose set forth.

JOHN M. ORAM.

\Vitnesses: r

' T. S. MILLER,

ALFRED H. BENNERS. 

